使用指针数组解决字符串排序问题

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
void change(char** a, char** b) {
    char *pt;
    pt = *a;
    *a = *b;
    *b = pt;
}
int main() {
    int i = 0, n = 0;
    char* s[20] = { NULL };

    for (; ; i++) {
        s[i] = (char*)malloc(sizeof(char) * 20);
        scanf("%s", s[i]);
        if (s[i][0] == '#')//指针数组其实就相当于一个二维数组；
        {
            n = i;
            break;
        }
    }
    //all correct；
    for (int j = 0; j < n; j++) {
        for (int k = j + 1; k < n; k++) {
            if (strlen(s[j]) > strlen(s[k]))
                change(&s[j], &s[k]);
        }
    }